Term
What factors can food choices be based on? |
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Definition
Personal Preference (#1 reason people choose food is based on taste) Habit Ethnic Heritage Social Interactions Availability/Economy Positive/Negative Associations Body Weight/Nutritional Benefits |
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Term
What is the #1 reason people choose a certain food? |
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Definition
Based on TASTE (Personal Preference) |
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Term
What are functional foods (designer foods)? |
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Definition
Foods that provide benefits BEYOND nutrients; physiologically active components provide extra health benefits
E.g. Oatmeal - has dietary fibre & lowers cholesterol |
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Term
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Definition
A produce that is ISOLATED/PURIFIED from foods generally sold in some medicinal form and has some demonstrated physiological benefit |
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Term
Difference between nutraceuticals/functional foods? |
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Definition
Functional foods - sold as food products Nutraceuticals - sold as medicinal products (isolates from food that are not sold as conventional foods) |
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Term
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Definition
NON-NUTRIENT compounds in PLANT derived foods with biological activity
E.g. Capsacin - in hot peppers, affects blood clotting |
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Term
What are the 6 classes of nutrients? |
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Definition
Carbohydrates, Lipids, Fats Vitamins Minerals Water |
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Term
What are the two simplest classes of nutrients? |
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Definition
Minerals (simplest; single elements) and then water (one molecule) |
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Term
Which nutrients are INORGANIC? |
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Definition
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Term
What are the only class of nutrients that have nitrogen? |
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Definition
Proteins (in amino groups) |
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Term
Differences between MACRO and MICRONUTRIENTS? |
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Definition
MACRO - lipids, carbs, proteins; required in GRAM amounts daily
MICRO - minerals, vitamins; required in mg/ug daily |
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Term
Energy density of the 3 macronutrients... |
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Definition
Carbs = 4 kcal/g Proteins = 4 kcal/g Lipids = 9 kcal/g |
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Term
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Definition
7 kcal/g; NOT a nutrient because it interferes with growth & repair processes in the body |
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Term
Fat vs. water soluble vitamins? |
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Definition
FAT SOLUBLE = A, D, E, K
WATER SOLUBLE = B, C |
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Term
How many essential minerals are there for the human body? |
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Definition
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Term
Which are more resilient to damage vitamins or minerals? |
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Definition
Minerals, b/c they are inorganic |
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Term
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Definition
Observe epidemiological statistics of ONE GROUP of people at ONE TIME in one population |
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Term
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Definition
Analyze data collected from a cohort of a population at intervals over time (longitudinal) |
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Term
What are the 4 DRI's (Dietary Reference Intakes)? |
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Definition
Estimated Average Requirement - EAR Recommended Dietary Allowance - RDA Adequate Intake - AI Tolerable Upper Limit - UL |
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Term
Definition of EAR and RDA |
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Definition
Estimated Average Requirement - average amount of nutrient that will be sufficient for 1/2 of the HEALTHY people in a given population
Recommended Dietary Allowance - average daily amount of nutrient considered to be adequate for the needs of 98% of healthy people in a population; "goal of nutrient intake" |
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Term
How are the RDA and EAR related mathematically? |
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Definition
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Term
When is the AI used? How is it determined? |
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Definition
AI - used when the RDA for a certain nutrient cannot be established
RDA is based on scientific evidence; but AI relies on judgments due to a LACK of evidence (covers unknown # of people) |
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Term
What is the estimated energy requirement? |
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Definition
average caloric intake needed to maintain energy balance in healthy person w/ average physical activity
EER is NOT as generous as the RDA/AI, because excess energy leads to weight gain/obesity |
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Term
AMDRs for the macronutrients... |
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Definition
Carbs = 45-65% Lipids = 20-35% Proteins = 10-35% |
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Term
What are anthropometric measures? |
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Definition
Measurements of physical characteristics (height, weight, etc.) |
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Term
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Definition
Condition/behaviour associated with elevated frequency of disease, but NOT necessarily causal |
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Term
Difference between RD and nutritionist in ontario? |
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Definition
RD needs to be licensed (undergrad program, internship, national exam), nutritionist does NOT need to be licensed or regulated by law |
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Term
6 key diet planning principles? |
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Definition
Adequacy Balance Calorie Control Nutrient Density (want high nutrient density; nutrients/kcal) Moderation Variety |
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Term
What is the 1 other group besides the 4 main groups in the Food Guide? |
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Definition
Oils & fats - 30-45 mL unsaturated fat each day |
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Term
Learn food guide groups again... |
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Definition
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|
Term
Learn make each food guide serving count guidelines... |
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Definition
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Term
What are the 2 types of labels on nutrition claims? What do they each represent? |
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Definition
Nutrition Content Claims - specific nutrient features of food with certain adjectives (light, free, low, less etc.)
Diet Related Health Claims - highlight relationship about food and person's health (reduce risk of disease, etc.) |
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Term
What are listed on the nutrition facts label? |
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Definition
Calories + 13 core nutrients on all facts tables |
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Term
What are the four/five main tastes? |
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Definition
Sweet, salty, sour, bitter, umami |
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Term
What happens to taste bud # with age? |
|
Definition
Declines; children have the most discerning taste |
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Term
Difference of taste vs. flavour? |
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Definition
Taste - the chemical sensations of food on the taste buds
Flavour - TOTAL sensory impression (taste, odour, mouthfeel); taste is a component of flavour |
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Term
|
Definition
Failure of LES to relax during swallowing; food builds up in the esophagus b/c it cannot enter the stomach |
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|
Term
|
Definition
From superior to inferior -> fundus, body, antrum |
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|
Term
|
Definition
Approx 50 mL when empty; can increase to 1L after a meal |
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Term
Are any nutrients absorbed in the stomach? |
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Definition
NO - no food or water absorbed here
Get a small amount of EtOH/ASA absorbed (but not nutrients) |
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Term
|
Definition
Substance released in small intestine in response to the presence of CHYME - stimulates pancreatic secretions into duodenum |
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|
Term
Where is vitamin D activated? |
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Definition
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|
Term
What is the liver's main contribution to digestion? |
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Definition
BILE production; bile is produced constantly by the liver; stored in gall bladder in between meals |
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Term
Where is the Spincter of Oddi? |
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Definition
At the duodenal papilla; opening of the common bile duct into the duodenum
Closed in between meals |
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|
Term
What is the primary method of movement in the large intestine? |
|
Definition
HAUSTRAL CONTRACTIONS - occur every 30 minutes |
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|
Term
How often to mass movements in the colon occur? |
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Definition
3 to 4 times per day (moves contents 1/3 to 3/4 the length of the colon in a few seconds) |
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|
Term
What GI organ has the thickest/strongest muscles? |
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Definition
The stomach - 3 layers (inner circular, middle oblique, outer longitudinal) |
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Term
Components of saliva (chemicals) |
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Definition
Salivary amylase & lipase; mucus; lysozyme |
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|
Term
|
Definition
Decrease in saliva production |
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|
Term
Where is salivary amylase inactivated? |
|
Definition
|
|
Term
|
Definition
Gastrin secreted when food enters stomach; stimulates HCl secretion; gastrin secretion is stopped when pH = 1.5 (very acidic)
HCl activates the pepsinogen zymogen to active pepsin (protein digestion) |
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|
Term
What is the primary function of secretin? |
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Definition
To maintain pH of duodenal contents; need to maintain a slightly alkaline pH for optimal pancreatic enzyme function |
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|
Term
What stimulates CCK secretion from the intestinal wall? |
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Definition
CCK secreted in response to protein OR fat in the lumen; causes gall bladder contraction to release bile and pancreas to release pancreatic juices
Also slows GI motility to increase time for digestion
3 main targets - gall bladder, pancreas, intestinal wall |
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|
Term
What types of membrane transport are used for different types of nutrient absorption? |
|
Definition
Simple diffusion - water & small lipids Facilitated diffusion - water soluble vitamins Active transport - glucose + aa's |
|
|
Term
who's doing a bad job of watching laptops |
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Definition
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|
Term
Food combining w/ vitamin C and Fe |
|
Definition
Vitamin C can actually enhance Fe absorption |
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|
Term
When can absorption be limited by simultaneously consuming other foods (food combining myth exception)? |
|
Definition
Phytates (legumes) may impair absorption |
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|
Term
|
Definition
Absorbed into lymphatic system (includes lipids, fat-soluble vitamins) and BYPASS the liver; enter the circulation at the L subclavian vein, down to the heart, where they are distributed throughout the body |
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|
Term
Lymphatic capillaries = ? |
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Definition
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Term
What direction is fluid flow in lymph? |
|
Definition
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|
Term
Difference between PROBIOTICS & PREBIOTICS? |
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Definition
PRO - living microbes found in food that are beneficial for health
PRE - foods NOT digested (e.g. fibre) that promote bacterial growth by acting as a food source |
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|
Term
What macromolecules take the longest to digest? |
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Definition
Fats & proteins (this is why CCK slows gastric motility) |
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|
Term
|
Definition
When osmotically active non-absorbable solutes remain in bowels where they retain water (pull water into colon); happens with lactose intolerance (lactose pulls water in), poorly absorbed salts |
|
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Term
|
Definition
ACTIVE secretion of salts and water; often due to bacterial toxins/viruses |
|
|
Term
|
Definition
Severe dehydration Hypokalemia, hypomagnesemia, hyponatremia Metabolic acidosis - loss of bicarb ions |
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|
Term
Why should antacids only be taken infrequently? |
|
Definition
Can weaken mucus barrier of GI tract |
|
|
Term
|
Definition
Stomach-like mucosa replaces epithelium in distal esophagus; usually due to healing phase of esophagitis; increases risk of esophageal cancer |
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|
Term
3 major causes of ulcers? |
|
Definition
H. pylori infection Use of certain anti-inflammatories - aspirin (ASA), naproxen, ibuprofen Excess gastric acid secretion |
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|
Term
What is a food borne illness "outbreak"? |
|
Definition
Two or more causes of a similar illness resulting from the ingestion of a common food |
|
|
Term
In terms of food borne disease, what is the major cause of illness and the major cause of death? |
|
Definition
Salmonella = major cause of illness
Listeria = major cause of death |
|
|
Term
What is the danger zone for food? |
|
Definition
DO NOT keep foods between 40-140 degrees F for more than 2 hrs; or more than 1 hr if air temp. is greater than 90 deg F |
|
|
Term
Hep A (food borne INFECTION) |
|
Definition
Sources - raw shellfish; veggies & fruits; contaminated H2O
Onset - 2-7 weeks; fever, loss of appetite, jaundice |
|
|
Term
Listeria (food borne INFECTION) |
|
Definition
Major cause of death from food borne infection; growth stopped by freezing From L. monocytogenes bacteria Onset = 1-70 days; mimics the flu, pregnancy complications, blood poisoning |
|
|
Term
Perfringens (food borne INFECTION) |
|
Definition
"Cafeteria germ"; multiplies in foods on steam tables/foods at room T
Onset = 8-16 hours; abdominal pain & diarrhea |
|
|
Term
Salmonellosis (food borne INFECTION) |
|
Definition
Onset = 1-3 days; can be fatal |
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|
Term
Botulism (food INTOXICATION) |
|
Definition
From C. botulinum; anaerobe in low acid environments
Onset = 4-36 hours; digestive problems, CNS complications, respiratory
Need to steam pressure cans to eliminate all spores |
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|
Term
S. aureus (food borne intoxication) |
|
Definition
Staph toxin - found in salads & cream soups; found endogenously in nasal passages
Onset = 1-6 hours; digestive symptoms; rarely fatal |
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|
Term
Safe internal temperatures - medium rare, chicken/turkey whole, middle range? |
|
Definition
Medium rare = 63 deg C
Chicken/turkey whole = 85 deg C
Middle range = 71-74 deg C |
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|
Term
What is the sweetest monosaccharide? |
|
Definition
Fructose (next is glucose, then galactose) |
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|
Term
What are the 3 disaccharides (and what are they made of)? |
|
Definition
Sucrose = fructose + glucose Maltose = glucose + glucose Lactose = galactose + glucose |
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|
Term
What is the glycogen distribution within the body? |
|
Definition
2/3 stored in muscles, 1/3 in liver |
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|
Term
Is glycogen branched or unbranched? |
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Definition
Branched; b/c it is branched, more rapidly hydrolyzed (lots of places for enzymes to attack) |
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|
Term
Branched starch vs. unbranched starch? |
|
Definition
Amylopectin (BRANCHED)
Amylose (UNBRANCHED) |
|
|
Term
What is different between cellulose and starch? |
|
Definition
The linkages that exist between the glucose monomers; we can digest starch, but not cellulose |
|
|
Term
Are most dietary fibres non-starch polysaccharides or non-polysaccharides? |
|
Definition
NON-STARCH P's; however, cannot be digested by the body b/c of the linkages between the glucose monomers |
|
|
Term
Non-starch polysacc vs. non-polysacc.... |
|
Definition
Non-starch = cellulose, hemicellulose, pectins, mucilages
Non-polysacc = lignins, tannins, cutins |
|
|
Term
Differences between soluble and insoluble fibers? |
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Definition
Soluble = form gels and can be digested by colonic bacteria (fermentable); oats, barley, legumes; viscous (form gel)
Insoluble = less readily fermented & no gel; whole grains (bran), lignins, cellulose, most hemicellulose; promote bowel movements b/c keep water in GI tract |
|
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Term
|
Definition
Starches classified as dietary fibre because they escape digestion & absorption in the small intestine |
|
|
Term
|
Definition
NOT a dietary fiber, but found in many of the same foods as soluble fibres
Dietary fiber, or phytic acid, binds to minerals to impair their absorption; only a serious concern if fiber intake is excessive |
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|
Term
AI for Fibre Intake Males vs. Females |
|
Definition
M = 38 g (19-50); 30 g (51+)
W = 25 g (19-50); 21 g (51+) |
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|
Term
Benefits of fibre in the diet? |
|
Definition
Strengthen intestinal walls - prevent diverticula formation Slow glucose absorption; promote satiety Prevents heart disease (lower BP improve blood lipids); soluble fibers increase excretion of bile salts to lower cholesterol |
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|
Term
How does fibre promote satiety? |
|
Definition
It lingers in the stomach to delay gastric emptying |
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|
Term
Absorption of the monosaccharides? |
|
Definition
Glucose + Galactose = enter cells by ACTIVE TRANSPORT
Fructose = absorbed by FACILITATED DIFFUSION; takes longer to absorb |
|
|
Term
What are the percentages of people in the world who have enough lactase to properly digest lactose? |
|
Definition
30% - have sufficient lactase 70% - have some sort of a deficiency |
|
|
Term
Lactose intolerance - prevalence (where is it highest, lowest?) |
|
Definition
Highest - native americans & southeast asians
Lowest - Scandinavians & northern europeans |
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|
Term
How much lactose can be consumed, by people with intolerance, that can be tolerated? |
|
Definition
Can usually tolerate 1/2 cup of milk (6 grams lactose) |
|
|
Term
|
Definition
Fermented milk that is lactose free (use L. acidophilus to breakdown lactose into glucose + galactose) |
|
|
Term
How long can glycogen stores in the liver last for? |
|
Definition
HOURS, not days; need to frequently consume dietary carbs to meet needs |
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|
Term
Conversion of protein to glucose is called? |
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Definition
GLUCONEOGENESIS (making glucose from a non-carbohydrate source, in this case protein) |
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|
Term
Alternate energy source for the brain (other than glucose)? |
|
Definition
Ketone bodies - formed from fats; excess results in metabolic acidosis |
|
|
Term
What processes are stimulated by insulin? |
|
Definition
Glucose uptake into ells Glycogen synthesis in the liver Conversion of excess glucose (if glycogen at max) into fat |
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|
Term
What is the fasting blood glucose in a healthy vs. diabetic individual? |
|
Definition
Healthy = 100-125 mg/dL (4-6 mM)
Diabetic = >126 mg/dL (>6mM) |
|
|
Term
What type of glycemic response do we want? What type of response do diabetics have? |
|
Definition
LOW GLYCEMIC RESPONSE - slow absorption, modest rise and slow return in blood glucose levels
Diabetics typically have a high glycemic response |
|
|
Term
What is more common DM I or DM II? |
|
Definition
DM II (90% of cases); vs. DM I (10%) |
|
|
Term
What may account for the increasing incidence of DM II in the population? |
|
Definition
Aging population Obesity rates rising coupled with sedentary lifestyles Aboriginal people are more likely to develop; new immigrants are from higher risk populations (Hispanic, Asian, African) |
|
|
Term
Structure of kernels in cereal grain? |
|
Definition
Brain = pericarp; outer portion; mainly cellulose, removed in milling
Endosperm = inner part; grains in protein matrix, usually used in refined flower
Germ = embryo; majority of fat located here |
|
|
Term
What is couscous made from? |
|
Definition
Semolina & water; NOT a grain, but still considered a pasta product |
|
|
Term
What type of reaction occurs in celiac disease? |
|
Definition
See an IMMUNE REACTION to gluten -> hypersensitivity reaction causing villi damage in the intestine |
|
|
Term
How to treat celiac disease? |
|
Definition
Need to completely remove gluten from diet; also need to eliminate lactose to taper flare-ups |
|
|
Term
|
Definition
200x sweeter than sucrose; widely used in canada
NOT absorbed or digested therefore NON-NUTRITIVE |
|
|
Term
Aspartame (Nutrasweet, Equal) |
|
Definition
200x sweeter than sucrose
Contains 2 aa's - Phe+Asp+Methyl group; does provide 4 kcal/g, but so much less than 1 g that it is irrelevant (debate about artificial sweetener vs. non-nutritive) |
|
|
Term
Which group of people cannot eat Aspartame? |
|
Definition
People with PKU, because they cannot digest Phenylalanine |
|
|
Term
|
Definition
30x sweeter than sucrose
Originally approved by FDA, then banned, now pending re-approval NOT added to foods, but sold as sweetener; heat stable |
|
|
Term
|
Definition
600x sweeter than sucrose
Made from sucrose, but replace OH with Cl; also heat stable; does not get absorbed, therefore NON-nutritive |
|
|
Term
|
Definition
NUTRITIVE sweetener (0.2-2.6 kcal/g)
Don't contribute to dental caries, have a small insulin response when ingested (provide energy) |
|
|
Term
|
Definition
Natural sweetener
Not added to foods, but can be sold for personal use |
|
|
Term
What 3 types of lipids exist? |
|
Definition
Sterols, Triglycerides, Phospholipids |
|
|
Term
Difference between fats & oils? |
|
Definition
Fats = lipids that are SOLID at room temp
Oils = lipids that are LIQUID at room temp |
|
|
Term
What # of C can fatty acids range in length from? Most common #? |
|
Definition
Range from 4 to 24 C; most common is 18 |
|
|
Term
|
Definition
Chain of C atoms with an acid group (carboxyl) at one end, and a methyl group at the other end |
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|
Term
Difference between omega-3 and omega-6 fatty acids? |
|
Definition
Omega-3 - double bond is between C3 and C4
Omega-6 - double bond is between C6-C7
They are numbered from the METHYL carbon |
|
|
Term
Difference between oleic, linoleic, linolenic, and stearic acid...? |
|
Definition
Oleic = 18 carbon monounsaturated Linoleic = 18 C polyunsaturated (2 double bonds) Linolenic = 18 C polyunsaturated (3 double bonds) Stearic = 18 C saturated |
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|
Term
What is the simplest 18C fatty acid? |
|
Definition
Stearic Acid = 18C saturated FA |
|
|
Term
What are the different lengths of FA chains? (e.g. LCFA, MCFA, SCFA) |
|
Definition
LCFA = 12-24 C; most common in MEAT MCFA = 6-10 C; most common in DAIRY SCFA <6 C; most common in DAIRY |
|
|
Term
What type of lipids are the majority in the body? |
|
Definition
TRIGLYCERIDES (99% of lipids in the body are triglyc) |
|
|
Term
What does the degree of unsaturation affect? |
|
Definition
Firmness - more saturated = less firm; less saturated = more firm
Stability = polyun FA's are more prone to oxidation (more readily go rancid) |
|
|
Term
What type of FA's are the most vs. least firm? |
|
Definition
Most firm = long, unsaturated
Least firm = short, saturated |
|
|
Term
What factors affect the firmness of an FA? |
|
Definition
Degree of saturation = more firm FAs are unsaturated, less firm are saturated
Length of C chain = more firm FAs are long, less firm are short |
|
|
Term
Why is excess trans fat consumption bad for your health? |
|
Definition
Increases LDL and decreases HDL |
|
|
Term
Where can you find omega 6 poly unsat vs. omega 3 polyunsat fats? |
|
Definition
Omega 6 - soybean oil, walnut oil, sunflower oil
Omega 3 - flaxseed oil, fish oil |
|
|
Term
What dietary fats have the highest vs. lowest percentage of monounsaturated/saturated fat? |
|
Definition
HIGHEST for saturated = coconut oil & butter fat
HIGHEST for monounsaturated = canola oil & safflower oil |
|
|
Term
What type of lipid is lecithin? Is it essential? |
|
Definition
Lecithin is a phospholipid; made in the liver, therefore non-essential |
|
|
Term
Difference between triglyceride vs. phospholipid? |
|
Definition
In phospholipid, have 1 FA replaced with a phosphate group + nitrogen containing compound |
|
|
Term
How many carbon rings are present in sterols? |
|
Definition
|
|
Term
How do phytosterols reduce cholesterol levels? |
|
Definition
Phytosterols compete with cholesterol for absorption; less cholesterol is absorbed and therefore more is excreted |
|
|
Term
Amount of cholesterol ingested daily vs. amount made endogenously? |
|
Definition
Ingested = 200-350 mg
Made endogenously = 800-1500 mg |
|
|
Term
Why is bile needed as an emulsifying agent? |
|
Definition
Lipids are hydrophobic, lipases are hydrophilic - need hydrophilic environment to digest the lipids |
|
|
Term
Difference between lingual lipase and salivary amylase in the STOMACH? |
|
Definition
Lingual lipase is acid stable, therefore is not inactivated by gastric acid
Salivary amylase is not acid stable and is inactivated in the stomach |
|
|
Term
Do you have lipase enz in the mouth & stomach? |
|
Definition
YES (lingual lipase & gastric lipase) |
|
|
Term
Differences in lipid absorption? |
|
Definition
SCFA, MCFA, glycerol - diffuse through cells to enter villi
LCFA, monoglycerides - surrounded by bile acids to form micelles |
|
|
Term
Name of lipoprotein transport vehicles? |
|
Definition
|
|
Term
What are the 4 main types of lipoproteins? |
|
Definition
Chylomicrons, LDL, HDL, VLDL |
|
|
Term
What lipoproteins are the largest and least dense? |
|
Definition
|
|
Term
Where is VLDL synthesized? |
|
Definition
|
|
Term
|
Definition
Travel throughout body and remove TGs; as more TGs are bound, VLDL turns into LDL |
|
|
Term
What is contained in circulating LDLs? |
|
Definition
Cholesterol, TGs, phospholipids |
|
|
Term
Which lipoproteins are important for the REVERSE CHOLESTEROL TRANSPORT/SCAVENGER pathway? |
|
Definition
HDL - made by liver to pick up cholesterol from cells and bring to liver for disposal |
|
|
Term
Relationship between saturated fat & LDL? |
|
Definition
Dose response curve; increased saturated FAs in diet correlate with increased LDL levels (vice versa with decreased saturated FA intake) |
|
|
Term
Effects of monounsaturated fatty acid intake on lipoprotein levels? |
|
Definition
LOWER LDL levels
DO NOT lower HDL levels, or raise triglycerides |
|
|
Term
Effects of polyunsaturated fat intake on lipoprotein levels? |
|
Definition
Similar to monounsat., lower LDL levels, but can also reduce HDL (not as good as monounsat., which has no effect on HDL) |
|
|
Term
|
Definition
LINOLEIC - omega 6 fatty acid; 18C, 1 double bond
LINOLENIC - omega 3 fatty acid; 18C, 2 double bonds |
|
|
Term
What is the relevance of the omega 6 to omega 3 FA ratio? |
|
Definition
Both of these FAs compete for the same ENZ
General consensus - increase OMEGA 3 in diet (not just ratio, increase actual amount) |
|
|
Term
Function of lipoprotein lipase? |
|
Definition
Hydrolyze TGs from VLDL/chylomicrons into di & monoglycerides and fatty acids
Once inside cells, reassemble into TGs for storage |
|
|
Term
What % of the body's energy needs at rest come from fat? |
|
Definition
|
|
Term
Examples of fat replacers? What can they be made from? |
|
Definition
Dextrin, maltodextrin, modified starch (examples)
Can be made from carbs, proteins, or fats |
|
|
Term
Difference between fat replacers & artifical fats? |
|
Definition
Fat replacers - replace some or all functions of fat; MAY OR MAY NOT provide energy
Artifical fats - ZERO ENERGY (non-nutritive); e.g. OLESTRA |
|
|
Term
Is Olestra a fat replacer or an artificial fat? |
|
Definition
Artificial Fat - no energy value |
|
|
Term
What is the structure of olestra? |
|
Definition
Sucrose bound to 6-8 LCFAs |
|
|
Term
What is a good source of omega 3 FAs? Monounsat? |
|
Definition
Omega 3 = fish/fish oil
Monounsat = canola oil, safflower oil, nuts |
|
|
Term
Characteristics of the Mediterranean diet? |
|
Definition
Low in saturated fat; very low in trans fa High in unsaturated fat, complex carbs, fibre, phytochemicals |
|
|
Term
# of essential vs. non essential aa's? |
|
Definition
9 essential, 11 non-essential |
|
|
Term
|
Definition
Gly, Ala, Pro, Tyr, Ser, Cys, Asn, Gln, Arg, Glu, Asp |
|
|
Term
|
Definition
Val, Leu, Ile, Met, Phe, Trp, Thr, His, Lys |
|
|
Term
What is the first enzyme to begin the zymogen activation cascade in the small intenstine? |
|
Definition
Enteropeptidase activates trypsinogen to trypsin; then it activates chymotrypsin & carboxypeptidases |
|
|
Term
Cleavage sites of TRYPSIN and CHYMOTRYPSIN? |
|
Definition
Trypsin - C terminal side of K and R
Chymotrypsin - C terminal side of F, Y, W, M, N, H |
|
|
Term
Nutritional misconception - ENZYMES in foods can help with digestion of food? |
|
Definition
FALSE - these enzymes are themselves digested so they cannot help |
|
|
Term
Nutrition misconceptions - amino acids are better to take than protein because they are easier to absorb? |
|
Definition
FALSE - body easily handles protein breakdown; one amino acid in excess can overwhelm a transporter |
|
|
Term
What does low plasma protein levels lead to? |
|
Definition
EDEMA - hydrostatic pressure pushes more plasma out of vessels than is drawn back in by osmotic pressure |
|
|
Term
What are protein related causes of edema? |
|
Definition
Excess protein loss Inadequate protein synthesis (liver disease) Inadequate consumption in the diet |
|
|
Term
What is the amino acid pool? |
|
Definition
Supply of TOTAL AMINO ACIDS in the body that can be incorporated into proteins/used for energy |
|
|
Term
What is nitrogen balance? |
|
Definition
In healthy individuals, want to maintain a nitrogen equilibrium (protein synth = protein breakdown) |
|
|
Term
|
Definition
Whether or not a particular protein provides enough ESSENTIAL AMINO ACIDS (only care about essential aa's) |
|
|
Term
What 2 things does protein quality depend on? |
|
Definition
Digestibility - # of amino acids that can be absorbed from a given protein intake; highest in animal food, lowest from plants
AA composition |
|
|
Term
What is the "limiting aa"? |
|
Definition
The ESSENTIAL aa that is supplied in less than the amount needed to support protein synthesis |
|
|
Term
What types of protein are generally higher in quality animals or plant? |
|
Definition
ANIMAL protein - more essential aa's in higher amounts, more aa's that can be absorbed |
|
|
Term
Protein Energy Malnutrition (+2 examples) |
|
Definition
PEM = protein and/or energy deficiency
E.g. = Marasmus, Kwarshiorkor |
|
|
Term
|
Definition
"Dying away"; CHRONIC PEM; severe deprivation of food over long-time |
|
|
Term
|
Definition
ACUTE PEM; rapid protein deficiency or secondary to illness |
|
|
Term
Effects of chronic vs. acute PEM on body appearance? |
|
Definition
ACUTE - results in children who are thin for their height (wasting); e.g. kwarshiorkor
CHRONIC - results in children who are short for their age (stunting); e.g. Marasmus |
|
|
Term
Effects of protein & fat intake and cancer risk? |
|
Definition
Elevated fat intake seems to be associated with higher cancer risk
Elevated protein intake does not seem to have an effect on cancer risk |
|
|
Term
What is the RDA for protein? |
|
Definition
0.8 g/kg of body weight per day for healthy males/females 19+ |
|
|
Term
What mineral absorption can phytates impair? Who is this particularly bad for? |
|
Definition
Phytates can impair Zn absorption; especially bad for vegetarians, need to be wary
Pescatarians can increase oyster, shrimp intake to account for Zn intake |
|
|
Term
|
Definition
Vit B12 is found ONLY in animal derived foods
Vegetarians can get it from tempeh (fermented soy w/ inactive B12) |
|
|
Term
What nutrient is MOST important to life? |
|
Definition
|
|
Term
What % of adult body weight does water account for? |
|
Definition
Approximately 60%
Makes up 3/4 weight of lean tissue; less than 1/4 weight of fat |
|
|
Term
Which groups of individuals have smaller % water weight? |
|
Definition
Females, elderly & obese
Females & obese due to higher % fat (water makes up less weight in fat tissue) |
|
|
Term
Distribution of water in the body (ICF vs. ECF)? |
|
Definition
ICF = 2/3 of water
ECF = 1/3 of water |
|
|
Term
What ions are more abundant in the ECF vs the ICF? |
|
Definition
ICF = phosphate, sulfate, potassium
ECF = sodium, chloride |
|
|
Term
|
Definition
A conscious desire to drink; usually lags BEHIND the body's need for H2O |
|
|
Term
When does the hypothalamus intiate thirst/drinking? When does it signal to stop? |
|
Definition
Start - When blood becomes more concentrated, when mouth is dry
Stop - When stretch receptors in stomach and volume receptors in heart signal |
|
|
Term
Symptoms of different water % body weight loss? |
|
Definition
1-2% = thirst, fatigue 3-4% = impaired physical performance, flushed skin, urine reduction 5-6% = impaired thinking, headache, increased respiration 7-10% = fainting, dizziness, spasms |
|
|
Term
|
Definition
When body water contents are TOO HIGH in all fluid compartments |
|
|
Term
How much water do we endogenously generate throughout the day? |
|
Definition
|
|
Term
Minimum volume of urine that must be excreted to carry out waste? |
|
Definition
|
|
Term
Sources of water loss in the body? |
|
Definition
GI tract, kidneys, skin (sweat), lungs (respiration) |
|
|
Term
How much of the daily water loss do the skin/lungs make up approx? |
|
Definition
|
|
Term
What is the average intake/output volume balance of water in the body |
|
Definition
|
|
Term
Water AI for men vs. women? |
|
Definition
Men = 3.7 L/day
Women = 2.7 L/day |
|
|
Term
What are the water recommendations for energy expenditure? |
|
Definition
1-1.5 mL/kcal in adults
1.5 mL/kcal in children/athletes |
|
|
Term
Difference between HARD and SOFT water? |
|
Definition
Hard = high in Mg and Ca
Soft = high in Na or K (Na usually added) |
|
|
Term
What physiological signals trigger ADH release? |
|
Definition
Low BV/BP; stimulates ADH release from pituitary - causes thirst & water retention from kidneys |
|
|
Term
Where is renin released from? Where is aldosterone secreted from? |
|
Definition
Renin - from kidney cells
Aldosterone - from adrenal glands |
|
|
Term
What is the effect of renin & aldosterone on the kidneys? |
|
Definition
Both stimulate Na+ reabsorption, leading to water following (get isosmotic fluid reabsorption) |
|
|
Term
Why water is able to help maintain body temperature? |
|
Definition
Has a high specific heat capacity - need lots of E to raise T of water |
|
|
Term
Conductivity of pure vs. ionized water? |
|
Definition
Pure water = poor conductor (no ions)
Ionized water = good conductor (dissolved ions carry charge) |
|
|
Term
What property of electrolytes helps them dissolve in water? |
|
Definition
Their ATTRACTION to the dipole present in water molecules (O is slightly negative, H is slightly positive) |
|
|
Term
Of all ions in the body, which are the most easily lost? |
|
Definition
Na and Cl - principal ions in the ECF |
|
|
Term
What kind of ion deficiency could a tumor causing excess aldosterone secretion cause? |
|
Definition
Hypokalemia (excess K+ secretion) |
|
|
Term
What 3 methods does the body use to regulate pH? |
|
Definition
1) Buffer systems (e.g. bicarb)
2) Respiratory rate (acute management)
3) Kidney excretion of ions (long term management) |
|
|
Term
What are the AI and UL of Na+? |
|
Definition
AI = 1500 mg
UL = 2300 mg = 1 teaspoon |
|
|
Term
What are the main ways that vitamins differ from the 3 macromolecules? |
|
Definition
1) Structure - are single units, not polymerized 2) Function - do NOT yield usable energy, but may be important in metabolism 3) Food contents - ingested in mg/ug amounts (not g) |
|
|
Term
|
Definition
Rate and extent to which a nutrient is absorbed & used |
|
|
Term
What does the amount of vitamins available from a given food depend on? |
|
Definition
1) Quantity present 2) Amount that can be absorbed/used by the body (bioavailability) |
|
|
Term
What is a provitamin? Example? |
|
Definition
Provitamin = inactive precursor of a vitamin
E.g. B-carotene is the provitamin of Vit A |
|
|
Term
What element can destroy Vit C? |
|
Definition
|
|
Term
How many water soluble vitamins are there? |
|
Definition
9 - thiamin, riboflav, niacin, biotin, B12, pantotenic acid, B6, folate, Vit C |
|
|
Term
Why must water soluble vitamins be obtained fairly regularly? |
|
Definition
Because any excess are filtered out by the kidneys fairly regularly |
|
|
Term
Can all substances be "toxic"? |
|
Definition
YES. ALL substances can be toxic if high enough/excessive enough concentrations are used |
|
|
Term
Difference in absorption between water soluble & fat soluble vitamins? |
|
Definition
Water soluble = directly into blood Fat soluble = first into lymph, then into blood (after bypassing the liver) |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
Which B vitamin is thiamin? |
|
Definition
|
|
Term
Functions of thiamin in the body? |
|
Definition
- Part of coenzyme TTP (energy metabolism)
- Occupies site on neuronal membrane |
|
|
Term
What B vitamin deficiency is common in alcoholics? Why? |
|
Definition
Thiamin (B1)
Common b/c - alcohol gives energy, rather than nutritious foods; alcohol impairs B1 absorption; alcohol enhances B1 excretion in the urine |
|
|
Term
Severe thiamin deficiency in alcoholics is called....? Symptoms? |
|
Definition
Wernicke-Korsakoff Syndrome
Disorientation, memory loss, staggering gait |
|
|
Term
What is thiamin deficiency (non-alcoholic) called? What are the different types? |
|
Definition
Beri beri (B1 deficiency)
Wet Beri Beri - with edema Dry Beri Beri - muscle wasting, no edema |
|
|
Term
When can thiamin degradation occur while cooking? |
|
Definition
Prolonged cooking & heating destroys thiamin - to preserve, cook with little water, steam or microwave for short periods |
|
|
Term
In what group of foods is thiamin virtually absent from? |
|
Definition
REFINED foods (is present in small quantities in almost all nutritious foods) |
|
|
Term
What B vitamin is riboflavin? |
|
Definition
|
|
Term
Roles of riboflavin in the body? |
|
Definition
- Coenzyme in many energy metabolism rxns
- Coenzyme = FMN, FAD |
|
|
Term
Toxicity symptoms of thiamin and riboflavin? |
|
Definition
NO toxicity symptoms (no symptoms of B1 or B2 excess) |
|
|
Term
What can destroy riboflavin (B2)? |
|
Definition
Prolonged exposure to UV light or irradiation destroys structure
Contrasting with thiamin, riboflavin IS heat stable |
|
|
Term
What foods have the greatest contribution of riboflavin to the diet? |
|
Definition
Milk/milk products; also liver & whole grains are excellent sources |
|
|
Term
What are vitamins B1, B2, B3? |
|
Definition
B1 = thiamin B2 = riboflavin B3 = niacin |
|
|
Term
What are the differences between the two chemical structures of niacin? |
|
Definition
Niacin = nicotinic acid, nicotinamide
Nicotinic acid is converted to nicotinamide = major form in the blood |
|
|
Term
Roles of niacin in the body? |
|
Definition
Two main coenzyme forms = NAD, NADP (both for energy metabolism) |
|
|
Term
What is unique about niacin that separates it from other B vitamins? |
|
Definition
Can be synthesized in the body from Trp
1 mg niacin = 60 mg of Tryp (60 mg of Trp = 1 mg B3 = 1 Niacin equivalent) |
|
|
Term
Pellegra is the deficiency of which vitamin? |
|
Definition
NIACIN (B3) deficiency
Symptoms = 4 D's = diarrhea, dermatitis, dementia, death
Observed in early 1900s; high corn diet = lots of leucine; Leu inhibits Trp->B3 conversion |
|
|
Term
Large doses of Niacin & LDL? |
|
Definition
Large doses of Niacin has been shown to have a pharmaceutical effect which can lower LDL chol |
|
|
Term
Of Vit B1, B2, B3 which are heat stable? |
|
Definition
B2 (riboflavin) and B3 (niacin)
B1 degrades rapidly in heat |
|
|
Term
Which B-vitamin is Biotin? |
|
Definition
|
|
Term
|
Definition
|
|
Term
What food can induce a biotin deficiency? |
|
Definition
RARE; induced with RAW egg whites - contain AVIDIN (binds to biotin to prevent absorption)
Symptoms - skin rash, hair loss, neurolog impairment, depression |
|
|
Term
What B-vitamin is pantothenic acid? |
|
Definition
Vit B5 = pantothenic acid |
|
|
Term
What coenzyme is pantothenic acid part of? |
|
Definition
Coenzyme A (CoA) - important in more than 100 steps in energy metabolism rxns |
|
|
Term
General symptoms of pantothenic acid deficiency? |
|
Definition
Very rare; "general failure of all body systems" b/c CoA is so necessary for so many reactions |
|
|
Term
Destruction of pantothenic acid? |
|
Definition
Canning, freezing, refining |
|
|
Term
Alternate names of vitamin B6? |
|
Definition
Pyridoxine, pyridoxal, pyridoxamine |
|
|
Term
Roles of vitamin B6 in the body? |
|
Definition
Part of coenzymes PLP, PMP Helps make RBCs Helps convert Trp -> Niacin |
|
|
Term
Difference in STORAGE for most water soluble vit vs. vit B6? |
|
Definition
Vit B6 is stored extensively in muscle tissue |
|
|
Term
|
Definition
Early symptoms - confusion, depression Late symptoms - abnormal brainwaves, convulsions
May be induced with excess alcohol consumption; contributes to B6 destruction |
|
|
Term
Besides EtOH, what else can lead to B6 deficiency? |
|
Definition
Isonicotinic acid hydrazide - used as antibiotic for Tb growth; acts as a B6 antagonist (binds & inactivates B6) |
|
|
Term
Destruction of vitamin B6? |
|
Definition
|
|
Term
What is most "food folate" considered to be? |
|
Definition
Polyglutamate = "bound folate" |
|
|
Term
Difference between bound vs. free folate? |
|
Definition
Bound folate = polyglutamate
Free folate = monoglutamate; preferred absorption by small intestine |
|
|
Term
Difference between active vs. inactive folate? |
|
Definition
Inactive folate = monoglutamate w/ Me group attached |
|
|
Term
For the Me group to be removed to activate folate, what other B vitamin is necessary? |
|
Definition
|
|
Term
What is vulnerable about folate absorption? |
|
Definition
It is secreted back into the GI tract w/ bile, so it needs to be repeatedly reabsorbed; vulnerable to GI tract injuries
E.g. Can be lost from EtOH abuse (damages GI tract) |
|
|
Term
What are the Dietary Folate Calculations? |
|
Definition
100 mg from food + 100 mg from supplements
= 100+170 = 270 mg of DFE
** Fortified foods/supplements multiplied by 1.7 b/c of increased bioavailability** |
|
|
Term
Recommendations of folate (B9) intake? |
|
Definition
RDA for pregnant women > than other adults
Pregnant = 600 mg DFE Adults = 400 mg DFE |
|
|
Term
Risk of folate deficiency during pregnancy? |
|
Definition
Increased risk of NEURAL TUBE DEFECTS (e.g. spina bifida) |
|
|
Term
When does the incidence of neural tube defects increase vs. decrease? |
|
Definition
Increase = times of poverty, drought, famine
Decrease = times of prosperity |
|
|
Term
Folate deficiency pathology? |
|
Definition
Impairment of cell division & protein synthesis - problems replacing RBCs & GI tract epithelium
End up with macrocytic/megaloblastic anemia - large, immature, RBCs (cells cannot divide); reduced O2 carrying capacity of the blood? |
|
|
Term
Deficiency of which vitamin can lead to large, immature red blood cell pathology? |
|
Definition
|
|
Term
What are risk factors for folate deficiency? |
|
Definition
Infants fed goat milk (low in folate) Times of increased cell multiplication - pregnancy, cancer, chicken pox, burns, GI tract damage |
|
|
Term
What is the vitamin most vulnerable to drug interactions which lead to a secondary deficiency? |
|
Definition
|
|
Term
Relationship between folate & heart disease? |
|
Definition
Folate breaks down HOMOCYSTEINE - high levels of homocysteine = high risk of CHD and stroke
Folate in fortified food seems to decrease homocysteine levels, but not risk of MI, CVA, and CVD (no decrease in disease risk) |
|
|
Term
Relationship between Folate and Vit B12? |
|
Definition
Depend on each other for activation (B12 removes Me group to activate folate coenzyme; B12 needs this Me group to become activated) |
|
|
Term
|
Definition
HCl and pepsin release B12 from the proteins it is bound to in the food in the STOMACH B12 binds to intrinsic factor (secreted in stomach), in the small intestine B12-intrinsic factor complex recognized at the distal end of the small intestine and B12 is absorbed
B12 NEEDS TO be bound to intrinsic factor to be recognized for absorption |
|
|
Term
What does B12 deficiency usually result from? |
|
Definition
Deficiency in ABSORPTION, not a deficiency in INTAKE
Absorption deficiency due to either lack of HCl secretion, or lack of intrinsic factor |
|
|
Term
In what GI pathology is B12 absorption deficiency common? |
|
Definition
In ATROPHIC GASTRITIS (lack of healthy stomach cells, decreased production of HCl and intrinsic factor) |
|
|
Term
What is "pernicious anemia"? |
|
Definition
Blood disorder that reflects a Vit B12 deficiency caused by lack of intrinsic factor, characterized by large, immature RBCs (similar pathology as folate deficiency) |
|
|
Term
What happens if you given folate when B12 is needed? |
|
Definition
Both deficiencies appear normal to being with, but if a B12 deficiency is present, but folate is given instead, serious neurological conditions can occur |
|
|
Term
Toxicity with B vitamins? |
|
Definition
No toxicity seen with any of them according to lecture notes |
|
|
Term
B12 destruction, folate destruction? |
|
Definition
B12 = destroyed with any amount of microwave heating
Folate = destroyed with cooking, heat, etc. |
|
|
Term
Where is B12 bioavailability highest? |
|
Definition
In milk & fish
Is almost uniquely found in foods of ANIMAL sources |
|
|
Term
Cooperative functioning of B vitamins - B2, B6, B3? |
|
Definition
B2 = riboflavin, B6 = pyridoxal, B3 = niacin
B2 coenz = FMN; assists ENZ to convert B6 to PLP Need both B2 and B6 for the conversion of Trp to Niacin |
|
|
Term
Choline - what up with that? |
|
Definition
Is a vitamin-like compound that is essential in the diet Can be made from methionine, but synthesis is insufficient without dietary consumption (essential)
Used by body to make ACh and lecithin (phospholipid) |
|
|
Term
Difference between inositol/carnitine & choline as vitamin like compounds? |
|
Definition
Inositol/carnitine = made by the body in sufficient amounts (non-essential)
Choline = not synth in sufficient amounts by the body (essential) |
|
|
Term
Functions of inositol and carnitine? What type of compounds are they classified as? |
|
Definition
Classified as non-essential vitamin like compounds
Inositol = part of CM structures; part of IP3 2nd messenger Carnitine = transport LCFAs from cytosol to mitochondria for oxidation |
|
|
Term
Alternate name for vitamin C? |
|
Definition
|
|
Term
|
Definition
Antioxidant - prevent against oxidative stress Cofactor in collagen synthesis (collagen = CT needed for tendons, ligs, bones, teeth) Cofactor in other reactions Levels increase during stress |
|
|
Term
What reactions does Vit C act as a cofactor in? |
|
Definition
Collagen syntheiss Trp to Serotonin (5-HT) conversion Tyr to Norepinephrine conversion
Assists in making hormones -> synthesis of thyroxine |
|
|
Term
Where is the most vitamin C stored in the body? |
|
Definition
|
|
Term
What reactions may mediate vitamin C's ability to treat the common cold? |
|
Definition
Deactivates histamine (similar to an anti-histamine) |
|
|
Term
Why is vitamin C difficult to study? |
|
Definition
Difficult to study in Canada and USA b/c it is usually present enough in diets for optimal health benefits (i.e. very few people are actually deficient naturally) |
|
|
Term
RDA and UL for Vitamin C? |
|
Definition
RDA women = 75 mg RDA men = 90 mg UL = 200 mg (max absorption)
For smokers, increase by 35 mg |
|
|
Term
When do symptoms of scurvy generally begin to appear (i.e. at what fraction of normal vitamin C levels)? |
|
Definition
At 1/5 optimal levels of vitamin C, symptoms of scurvy generally appear |
|
|
Term
|
Definition
Gums bleed around teeth, BV's under the skin break, hemorrhage due to collagen deficiency, muscle degeneration (including heart) |
|
|
Term
When does vitamin C toxicity typically arise? |
|
Definition
When people are taking large supplemental doses |
|
|
Term
What are "notoriously poor" sources of vitamin C? |
|
Definition
|
|
Term
What are the 3 active forms of vitamin A in the body? |
|
Definition
Retinol, retinal, retinoic acid (collectively are the "retinoids") |
|
|
Term
What are the 3 active forms of vitamin A in the body? |
|
Definition
Retinol, retinal, retinoic acid (collectively are the "retinoids") |
|
|
Term
Conversion between the active forms of vitamin A? |
|
Definition
3 in total - "retinoids" = retinol, retinal, retinoic acid
Retinol to retinal conversion is reversible Retinal to retinoic acid is NOT reversible |
|
|
Term
Vitamin A activity v.s NO vitamin A activity in CAROTENOIDS? |
|
Definition
ACTIVITY = alpha-carotene, beta-carotene, beta-cryptoxanithin
NO ACTIVITY = lycopene, lutein, zeaxanthin |
|
|
Term
Vitamin A equivalents from B-carotene? How many Vit A moc can be yielded from a B-carotene molecule? |
|
Definition
12 ug of B-carotene = 1 ug of Vitamin A
If cut in the MIDDLE, then get 2 moc of vit A; if cut elsewhere, only get 1 moc of vit A |
|
|
Term
Absorption of Vit A in the body? |
|
Definition
Absorbed into lymph (fat soluble)
Stored in liver; carried by retinol-binding protein in bloodstream |
|
|
Term
Major roles of vitamin A? |
|
Definition
Promote vision (maintains the cornea) Protein synthesis and cell differentiation Support reproduction & gowth |
|
|
Term
What protein in the eye is vitamin A part of? What is its function? |
|
Definition
Rhodopsin = pigment moc composed of opsin bonded to a molecule of retinal
When light strikes pigment, changes shape and becomes bleached; change to trans bond and impulse is sent to CNS; cis = active form; trans = inactive |
|
|
Term
In terms of vitamin A, which retinoid is a biological " chemical dead end" for the visual process? |
|
Definition
Retinoic acid
Visual activity leads to loss of retinal (converted to retinoic acid), and requires replenishment constantly |
|
|
Term
True or false - most of the body's vitamin A stores are in the retina? |
|
Definition
FALSE - only 1/1000th of vitamin A in the body is in the retina |
|
|
Term
Vitamin A's roles in reproduction, growth & cell differentiation? |
|
Definition
- Aids in maintaining healthy mucous membrane & epithelium - Aids in sperm cell development - Participates in bone remodelling |
|
|
Term
Symptoms of vitamin A deficiency? |
|
Definition
Infectious disease - many immune defenses rely on vit A Night blindness - early symptom; retina does not have enough retinal, so cannot adapt to bright lights/darkness TOTAL blindness - xeropthalmia |
|
|
Term
Difference in pathology of night blindness & total blindness (xerophthalmia) & vit A? |
|
Definition
Night blindness = lack of retinal at BACK of eye (retina)
Total blindness = lack of retinal at FRONT of eye (cornea) |
|
|
Term
Can B-carotene from foods lead to Vit A toxicity? |
|
Definition
NO - B-carotene from foods is NOT converted efficiently enough into Vitamin A to cause Vit A toxicity |
|
|
Term
Effects of excess vit A on the fetus? |
|
Definition
Can be TERATOGENIC - vit A toxicity can lead to birth defects (most damaging at high amounts before 7th week of pregnancy) |
|
|
Term
What foods are high in vitamin A? |
|
Definition
Liver, milk, fish liver oil, butter, eggs, fortified margarine |
|
|
Term
Of all the carotenoids which has the highest Vit A activity? |
|
Definition
B-carotene (most efficient conversion; 12 ug = 1 ug Vit A = 1 retinol activity equivalent) |
|
|
Term
Where is Vit D activated? |
|
Definition
Precursor from cholesterol converted by UV light
Activated in liver, then kdineys |
|
|
Term
Difference between Vit D2 vs. D3? |
|
Definition
D2 - plant foods D3 - animal foods & skin |
|
|
Term
|
Definition
|
|
Term
Which vitamins are members of the "bone making & maintenance team"? |
|
Definition
|
|
Term
How does vitamin D raise blood concentrations of certain minerals (calcium & phosphorus)? |
|
Definition
1) Enhance absorption from GI tract 2) Enhance reabsorption from kidneys 3) Enhance mobilization from bones to blood (bone breakdown) |
|
|
Term
What mineral deficiency can vit D deficiency lead to? |
|
Definition
Vit D deficiency can lead to a Ca deficiency (increases risk of osteoporosis) |
|
|
Term
Diseases of vitamin D deficiency? |
|
Definition
Rickets (deficiency in children; bowed legs, bone deformity, enlargements at ends of long bones) Osteomalacia (deficiency in adults; softening of bones) |
|
|
Term
Which vitamin is among the most likely to have toxic effects when consumed in excess? |
|
Definition
VITAMIN D - kidney stones, stenosis of arteries
* NO risk of excess from the sun |
|
|
Term
|
Definition
1000 IU supplements daily for fall & winter (adults)
1000 IU supplements YEAR ROUND for - elderly, dark skinned, stay indoors, etc. |
|
|
Term
Vitamin D recommendations in those w/ osteoporosis/high risk vs. no osteoporosis? |
|
Definition
w/ or high risk = 800-2000 IU supplement/day
NO osteo: - Below 50 = 400-1000 IU daily - Above 50 = 800-2000 IU daily |
|
|
Term
Guidelines for Vit D intake for supplements in ppl over 50 for Osteoporosis Canada vs. Health Canada? |
|
Definition
Osteoporosis Canada -> 800-2000 IU daily
Health Canada -> 400 IU daily |
|
|
Term
Alternate name for vitamin E? |
|
Definition
|
|
Term
Why are there 4 different tocopherols, but our body is only concerned with alpha? |
|
Definition
Alpha-t is the only one with activity in human body; other ones are NOT converted to alpha-t in human body |
|
|
Term
|
Definition
Antioxidant Protects polyunsat fatty acids May decrease oxidation of LDL to reduce risk of heart disease |
|
|
Term
What is vitamin E deficiency primarily due to? |
|
Definition
Usually due to diseases with fat malabsorption (e.g. cystic fibrosis), NOT due to poor intake most often |
|
|
Term
What blood condition is common with vitamin E deficiency? |
|
Definition
Erythrocyte Hemolysis - RBCs split open due to oxidation of polyunsat fats in membrane |
|
|
Term
Which toxicity is least common out of all the fat soluble vitamins? |
|
Definition
|
|
Term
What are the two forms of vitamin K? |
|
Definition
Phylloquinone (Natural form)
Menadione (Synthetic form) |
|
|
Term
Where can vitamin K be produced in the body? |
|
Definition
Can be produced by bacteria in GI tract; absorbed and stored in liver |
|
|
Term
Roles of vitamin K in the body? |
|
Definition
Activation of proteins involved in blood clotting (deficiency can cause hemorrhagic disease)
Participates in metabolism of bone proteins (e.g. osteocalcin); deficiency may cause decreased bone density |
|
|
Term
Why do newborns receive a dose of vitamin K? |
|
Definition
Due to a sterile GI tract (have no GI bacteria which can produce vitamin K endogenously) |
|
|
Term
What is the UL of vitamin K? |
|
Definition
NO established UL - toxicity is uncommon |
|
|
Term
What is the RDA/AI for Vit A? |
|
Definition
|
|
Term
What are the arguments against supplements of vitamins? |
|
Definition
Toxicity - excessive amounts Life threatening misinformation - people think high doses are therapies instead of seeking medical advice Unknown needs - no one knows ideal supplement False sense of security |
|
|
Term
Definition of osteoporosis? Most vulnerable areas? |
|
Definition
Metabolic bone disease characterized by low bone mass & micro-architectural deterioration of bone tissue w/ resulting increase in fragility fractures
Most fragile - hip, spine, wrist
Known as the "silent thief" - bone losses occur without symptoms |
|
|
Term
Osteoporosis is more prevalent in which gender over the age of 50? |
|
Definition
More prevalent in women (1/4 women vs 1/8 men over 50) |
|
|
Term
In what races is osteoporosis specifically common in in women > 50 yrs old? |
|
Definition
White women & asian women |
|
|
Term
Incidence of women vs. men of suffering osteoporotic fractures in their lives? |
|
Definition
Women = 1/3; men = 1/5
Fractures from osteoporosis are more common than heart attack, stroke, and breast cancer combined |
|
|
Term
How many hospital bed days are consumed by osteoporotic fractures? |
|
Definition
More bed days than stroke, diabetes & heart attack |
|
|
Term
Some of the symptoms of osteoporosis? |
|
Definition
Pain in joints/bones Reduced height Marked curvature of the spine (kyphosis = hunchback) |
|
|
Term
What is the greatest predictor for development of osteoporosis? |
|
Definition
FAMILY HISTORY of osteoporotic fracture (especially maternal hip fracture) |
|
|
Term
Modifiable osteoporosis risk factors? |
|
Definition
Low bone mineral density Low body weight High EtOH, smoking abuse Excess caffeine Diet - low Ca2+ intake |
|
|
Term
Bone Density
What 2 things is bone density determined by? |
|
Definition
Weight of mineral per volume of bone (largely determines strength of bone)
How many mineral atoms are deposited in bone matrix & how porous the matrix is |
|
|
Term
|
Definition
Dual energy x-ray absorptiometry - used to measure bone density (use to measure bone mineral density to determine likelihood of fractures) |
|
|
Term
At what age is young bone healthiest? |
|
Definition
|
|
Term
Normal Bone vs. Osteopenia vs. Osteoporosis T-scores (as measured by bone mineral density) |
|
Definition
Normal < -1 Osteopenia = between -1 and -2.5 Osteoporosis = worse than -2.5 (less than)
*Mean = average bone density of 25 yr old woman |
|
|
Term
How often is bone remodelling occurring in a healthy adult? |
|
Definition
|
|
Term
Effect of aging on bone remodelling? |
|
Definition
Bone system less efficient - osteoclasts break down bone faster than osteoblasts can rebuild Ca2+ absorbed less efficiently; less of an ability to activate Vit D by the kidneys, etc. |
|
|
Term
At what ages do bones stop growing in length in men vs. women? |
|
Definition
Men = 20 yrs old; Women = 16 yrs old
Are almost at peak bone mass |
|
|
Term
Can activity in childhood increase bone growth? |
|
Definition
Yes, active children have a 5-15% increase in growth |
|
|
Term
At which age is peak bone mass reached? |
|
Definition
|
|
Term
In their elder years who loses more bone, men or women? |
|
Definition
Women lose more bone (men only lose about 2/3 of what women lose)
*Women can lose up to 45% of bone mass throughout their lifetime |
|
|
Term
When do men start to typically experience accelerated bone loss? |
|
Definition
After the age of 65 (much later than in women) |
|
|
Term
What is a fragility fracture? |
|
Definition
Fracture that results from MINIMAL trauma, or no identifiable trauma at all (such as a fracture from a fall at standing height or less) |
|
|
Term
Are most low trauma spinal fractures symptomatic? |
|
Definition
NO. 60% of these fractures are ASYMPTOMATIC |
|
|
Term
Appropriate measurement of height? |
|
Definition
No shoes Heels, buttocks, & back against board, head forward Measure height after exhalation |
|
|
Term
How to identify thoracic vs. lumbar fractures? |
|
Definition
Thoracic - occiput to wall distance; > 5cm raises suspicion
Lumbar - rib-pelvis distance; distance between costal margin & pelvic rim; < 2 fingerbreadths raises suspicion |
|
|
Term
Care gap in osteoporosis & fractures? Key changes that have been made to address these discrepancies? |
|
Definition
Less than 20% of those with fragility fractures are treated & investigated for osteoporosis; vertebral fractures are consistently underdiagnosed
Increased focus on fragility fractures; increased focus on care gap in identification and treatment of high-risk individuals Paradigm shift - manage patient according to fracture risk, NOT BMD |
|
|
Term
A _______ is to osteoporosis what a heart attack is to cardiovascular disease. |
|
Definition
|
|
Term
What measurements are taken when assessing vertebral fractures? |
|
Definition
Overall height Rib to pelvis distance (lumbar fractures) Occiput to wall distance (thoracic fractures/kyphosis) |
|
|
Term
What is the target population for osteoporosis/fracture risk screening? |
|
Definition
Men & women over the age of 50 |
|
|
Term
Phamacologic therapies to prevent fractures? |
|
Definition
Bisphosphonates Anti-resorptives (prevent bone resorption) Parathyroid hormone |
|
|
Term
To most consistently improve clinical outcomes, what is the optimal serum level of 25-hydroxy Vit D? |
|
Definition
|
|
Term
What is the recommended daily calcium intake (in mg)? |
|
Definition
1200 mg per day (from diet + supplements combined) |
|
|
Term
What are the 10 year fracture risks for low risk, moderate risk, and high risk groups? |
|
Definition
Low < 10% (10 yr) Moderate (10-20%) (10 yr) High (>20%) (10 yr) |
|
|
Term
What are some of the potential risks of high Ca2+ supplementation? |
|
Definition
Renal calculi (kidney stones) in older women Cardiovascular events in older women (may be due to calcification of coronary arteries) Prostate cancer in older men |
|
|
Term
What is the "falls risk assessment" a good predictor for? |
|
Definition
Future falls (well that seemed obvious...) |
|
|
Term
How can moderate to vigorous physical activity help prevent future fractures? |
|
Definition
Places increased load on the bones -> bones respond by increasing in MASS Improves our balance & coordination, reduces falling risk |
|
|
Term
Physical activity to prevent osteoporosis includes both: |
|
Definition
Weight bearing - walking, line dancing, low impact aerobics
Strength training |
|
|
Term
What are the effects of exercise on bone density? |
|
Definition
NO improvement of bone density |
|
|
Term
High intensity vs. high impact exercise in osteoporotic individuals? |
|
Definition
Want high INTENSITY, high impact is not appropriate |
|
|
Term
What has happened to federal spending on physical activity recently? |
|
Definition
Peak in 1986, decreasing steadily to 2005, then improved (higher) in 2009 |
|
|
Term
Guidelines for safe movement in exercising? |
|
Definition
DO NOT bend forward; use knees instead of bending at waist Avoid twisting torso, avoids pressure on your spine |
|
|
Term
What is the main goal of good Ca2+ nutrition in individuals with osteoporosis? |
|
Definition
Maintain adequate supply so we do not have to dip into our only Ca2+ reservoir (our bones)
Ca2+ and Vit D are adjunct treatments, not sole treatments |
|
|
Term
Why are dairy sources best for calcium? |
|
Definition
Elemental content is greater Highest rate of absorption Low cost for greatest benefit |
|
|
Term
Calcium guidelines for people < 50 yrs vs. > 50 yrs? |
|
Definition
< 50 = 1000 mg
> 50 = 1200 mg |
|
|
Term
Most popular calcium supplement on the market? |
|
Definition
|
|
Term
Conversion of vitamin D in the liver vs. the kidney? |
|
Definition
In liver - becomes 25-hydroxy Vit D
In kidney - becomes 1, 25-dihydroxy Vit D (active form) |
|
|
Term
Effect of Mg intake on bone? |
|
Definition
|
|
Term
Lycopenes & osteoporosis? |
|
Definition
Contain carotenoids which are antioxidative - prevent cell damage from oxidative stress (free radicals can increase pathogenesis of osteop.) |
|
|
Term
Prevalence of osteoporosis in men > 50? |
|
Definition
1 in 8; decline in bone density is more gradual in men than women |
|
|
Term
Reasons why osteoporosis is less common in men? |
|
Definition
Men have greater peak bone mass Men do not experience accelerated loss at menopause like women Men do not live as long Men are less likely to fall than elderly women |
|
|
Term
Relative toxicity of EtOH compared to other alcohols? |
|
Definition
|
|
Term
How many organs are affected by alcohol? |
|
Definition
|
|
Term
Alcohol's effects on liver cells & fatty acid metabolism? |
|
Definition
Normally hepatocytes use FA's as fuel, pack excess TG's and ship out to other tissues When EtOH is present, FA's accumulate while the liver breaks down alcohol (impaired ability to metabolize fats) -> leads to fatty liver in heavy drinkers |
|
|
Term
Conversions of one standard drink (wine vs. hard liquor vs. beer)? |
|
Definition
142 mL wine (12%) = 43 mL hard liquor (40%) = 341 mL beer (5%) |
|
|
Term
|
Definition
40% (divide the proof by 1/2 to get the %) |
|
|
Term
In alcohol fermentation in yeast, each moc of fermented glucose yields? |
|
Definition
2 moc EtOH 2 moc CO2 2 moc H2O |
|
|
Term
When is fermentation complete in yeast? |
|
Definition
When the sugar (glucose) has been all used up OR enough EtOH has been produced to inactivate the yeast
* Sugar can be fermented in anaerobic conditions, so O2 is not needed |
|
|
Term
Why must maling occur in ethanol fermentation? |
|
Definition
Because yeast requires sugar, not starch -> need to break down starches into simple sugars for the yeast to use |
|
|
Term
What is unique about alcohol? |
|
Definition
Alcohol requires NO digestion; 10-30% of EtOH is absorbed directly from an empty stomach, can reach brain in 1 min |
|
|
Term
Where does alcohol breakdown begin & with what enzyme? |
|
Definition
Begins in the stomach with alcohol dehydrogenase (ADH) |
|
|
Term
Difference in alcohol breakdown in women vs. men? |
|
Definition
Women produce less ADH in the stomach, therefore more EtOH reaches the intestines for absorption than in men |
|
|
Term
Preferential treatment of EtOH in the intestine... |
|
Definition
Rapidly absorbed; gets absorbed/metabolized BEFORE most nutrients
Preferential treatment addresses the following - EtOH cannot be stored, it is potentially toxic |
|
|
Term
Processing capacity of EtOH by liver cells? |
|
Definition
Liver cells are the only other cells besides stomach cells that produce ADH at an appreciable enough level to breakdown EtOH
LIVER CAN PROCESS 1/2 ounce ethanol per hour (max rate of breakdown is determined by ADH levels present) |
|
|
Term
Why do you feel increased effects of EtOH when you have not eaten all day (2 reasons)? |
|
Definition
Increased EtOH absorption
Slowed EtOH breakdown (decreased ENZ from protein breakdown) |
|
|
Term
2 steps in the breakdown of alcohol... |
|
Definition
ADH - turns EtOH to acetaldehyde Acetaldehyde dehydrogenase - turns acetaldehyde into acetate (eventually converted to Acetyl-CoA) |
|
|
Term
What molecule is responsible for picking up the H+ ions produced by the dehydrogenation reactions of alcohol breakdown? |
|
Definition
NAD+ (becomes NADH, get accumulation of NADH when consuming alcohol) |
|
|
Term
Consequences of NADH accumulation during alcohol consumption... |
|
Definition
Accumulation of H+ ions decreses pH (acidity) Causes lactate production from pyruvate Slows TCA cycle, build-up of Acetyl CoA; this acetyl CoA becomes fatty acids, leading to "fatty liver" |
|
|
Term
What are the negative effects of EtOH intake in impairing normal liver function? |
|
Definition
Impaired Vit D activation Decreased bile production Decreased gluconeogenesis (making glucose from protein) |
|
|
Term
What is the first stage of liver deterioration? Is it reversible? |
|
Definition
1st stage = fatty liver
Yes it is reversible if one abstains from drinking |
|
|
Term
What are the 2nd and 3rd stages of liver disease related to excess alcohol consumption? |
|
Definition
2nd = FIBROSIS; still partially reversible
3rd = cirrhosis; hardening of hepatocytes and permanent loss of function |
|
|
Term
Effects of alcohol consumption and protein in the body? |
|
Definition
Impairs protein synthesis and metabolism, leads to protein depletion Increases formation of ketone bodies from deaminated amino acids in food Eating well WILL NOT protect a heavy drinker from protein depletion, need to stop drinking! |
|
|
Term
What is MEOS? What is its function? |
|
Definition
Microsomal ethanol-oxidizing system; handles 1/5 of EtOH and other drugs |
|
|
Term
Order of neural responses to alcohol consumption... |
|
Definition
1) Sedates frontal lobe to impair judgement & reasoning 2) Speech & vision centres in midbrain impaired 3) Voluntary muscle control affected 4) Respiration & heart rate are last to be affected |
|
|
Term
What pituitary hormone does EtOH consumption depress the release of? |
|
Definition
Anti-diuretic hormone (ADH) - leads to increased urine production and dehydration |
|
|
Term
How can alcohol abuse lead to folate deficiency? |
|
Definition
Liver loses ability to retain folate & kidneys increase folate excretion in urine Normally folate is excreted in bile and reabsorbed in intestines - intestines damaged & decreased folate absorption |
|
|
Term
Which vitamin deficiencies are seen with excess alcohol consumption? |
|
Definition
B9 - folate B1 - thiamin B6 - pyridoxal, pyridoxine B12 Vitamin D - lack of activation in liver Vitamin A - lack of activation in liver |
|
|
Term
Alcohol Consumption - Low Risk Drinking Guideline #1 |
|
Definition
No more than 10 drinks/week for women (no more than 2 drinks most days)
No more than 15 drinks/week for men (no more than 3 drinks most days) |
|
|
Term
Alcohol Consumption - Low Risk Drinking Guideline #2 |
|
Definition
Women - drink no more than 3 drinks on any given occasion Men - drink no more than 4 drinks on any given occasion |
|
|
Term
What are the major minerals present in the body? Most vs. least? |
|
Definition
7 in total - Ca, P, K, S, Na, Cl, Mg
Ca = most Mg = least |
|
|
Term
What are the "trace minerals" present in the body? |
|
Definition
|
|
Term
Minerals and cooking....what up with that |
|
Definition
CANNOT be destroyed by heat, acid or air
CAN leach into cooking water |
|
|
Term
Difference in handling between K and Ca in the body? |
|
Definition
K - easily absorbed, transported freely in blood Ca - requires binding protein for absorption and transportation |
|
|
Term
Nutrient interactions - Na/Ca and P/Mg |
|
Definition
Na/Ca - when Na intake is high, both are excreted together
P/Mg - P binds Mg to limit absorption |
|
|
Term
What is the AI for Na? UL?
What is its mean intake? |
|
Definition
1500 mg/day = AI
2300 mg/day = UL
Mean intake reported at 3400 mg/day |
|
|
Term
What is "salt sensitivity"? |
|
Definition
BP response to salt intake; if salt intake is high, high BP (increased); if salt intake is low, low BP (decreased) |
|
|
Term
Why is there an emphasis on fruits, vegetables, and low fat milk products in HTN risk individuals? |
|
Definition
|
|
Term
Is Na deficiency usually due to inadequate intake? |
|
Definition
NO. Usually do to sweating, vomiting, diarrhea |
|
|
Term
What are the immediate symptoms of Na+ toxicity? |
|
Definition
|
|
Term
What is the body's principle cation in the ECF? |
|
Definition
|
|
Term
Effect of K+ deficiency on BP? |
|
Definition
Low K+ intake seems to raise BP
High K+ intake seems to prevent and correct HTN (lower BP) |
|
|
Term
What is the most common electrolyte imbalance? |
|
Definition
|
|
Term
What is the most abundant mineral in the body? 2nd most? |
|
Definition
Most abundant = Ca2+
2nd most = phosphorus |
|
|
Term
Symptoms of calcium toxicity? |
|
Definition
Constipation Increased risk of renal calculi Interference of absorption of other minerals |
|
|
Term
Roles of P in the body (phosphorus)? |
|
Definition
85% found combined with Ca in bones & teeth Phosphoric acid as a buffer system Needed for DNA/RNA synth. Needed for activation of enzymes & B vitamins Phospholipids need phosphate groups |
|
|
Term
A diet adequate in ____ is usually adequate in phosphate |
|
Definition
PROTEIN (phosphate comes mainly from animal sources) |
|
|
Term
Where is most of the body's Mg stored? |
|
Definition
50% in the bones 1% in ECF 49% in muscles/soft tissues |
|
|
Term
What is the MAJOR role of Mg in the body? |
|
Definition
Catalyst for chemical reactions |
|
|
Term
Symptoms of Mg deficiency? |
|
Definition
Appears that people eat less than recommended, deficiency symptoms are rare Impaired CNS activity, hallucinations Growth failure in children |
|
|
Term
Different ionic states of Fe? |
|
Definition
Fe2+ = ferrous Fe3+ = ferric
Allows it to function as a cofactor in REDOX REACTIONS |
|
|
Term
Where is most of the body's iron found? |
|
Definition
Hb - in RBCs Myoglobin - in muscle cells
Helps accept & carry O2 in both |
|
|
Term
How is the Fe balance in the body primarily maintained? |
|
Definition
Through absorption (b/c not readily excreted)
Absorption fluctuates to meet needs - more absorbed if stores are low, less if stores are full |
|
|
Term
What is ferritin? What happens when Fe is needed by the body? |
|
Definition
Fe-storage protein
When needed, Fe is transported from ferritin to transferrin (from mucosal transferr. to blood transfer) |
|
|
Term
Difference in absorption between HEME and NON-HEME Fe? |
|
Definition
Heme = 25% absorbed
Non-heme = 17% absorbed |
|
|
Term
Differences between heme and non-heme iron? |
|
Definition
HEME: only from animal derived foods; small amount of dietary iron
NON-HEME: from plant & animal sources; accounts for MAJORITY of dietary iron |
|
|
Term
Which type of iron accounts for the majority of dietary Fe? |
|
Definition
NON-HEME (from animal or plant sources) |
|
|
Term
What factors present in foods can enhance Fe absorption? |
|
Definition
MFP factor, vitamin C, citric & lactic acids, HCl and sugars |
|
|
Term
What factors in the diet INHIBIT iron absorption? |
|
Definition
Phytates, vegetable proteins, polyphenols (coffee, tea, tannins), Ca2+ |
|
|
Term
Typically, is more iron absorbed from a mixed or a vegetarian diet? |
|
Definition
Mixed is more (18% absorption vs. 10% in veggie) |
|
|
Term
What are the most important factors present in meals that affect iron absorption? |
|
Definition
Vitamin C & MFP (enhance absorption)
Phytates (inhibit absorption) |
|
|
Term
Where most of the body's iron stored? |
|
Definition
In ferritin in the liver; also stored in bone marrow and spleen to a lesser degree |
|
|
Term
If Fe levels are abnormally high, what happens to ferritin (iron storage protein)? |
|
Definition
Converted to HEMOSIDERIN (releases iron more slowly than ferritin) |
|
|
Term
|
Definition
|
|
Term
What hormone regulates iron balance? |
|
Definition
HEPCIDIN - produced by liver; inhibits intestinal absorption, release from liver, speen and bone marrow |
|
|
Term
What is the most common nutrient deficiency in the world? |
|
Definition
|
|
Term
What are the 3 stages of iron deficiency? |
|
Definition
1) Iron stores diminish - decrease in serum ferritin 2) Decreased transport of Fe - decrease in transferrin 3) Limited Hb production - HGB |
|
|
Term
Why are iron deficiency and iron deficiency anemia not always the same? |
|
Definition
Fe deficiency - depleted iron stores in the body
Fe deficiency anemia - depleted Fe stores that RESULT IN a low [Hb]; RBCs appear hypochromic (pale) and small (microcytic) |
|
|
Term
Appearance of RBCs in iron deficiency anemia? |
|
Definition
Microcytic (small) and hypochromic (pale)
Can't carry enough O2 because of low [Hb] |
|
|
Term
|
Definition
Pica = craving of NON food substances = clay, chalk, ice
Seen in some iron deficient people |
|
|
Term
What genetic condition can result in iron overload/toxicity? |
|
Definition
Hemochromatosis - iron absorption does NOT decrease when iron is not neeeded, builds up to an excess |
|
|
Term
What form is iron in in supplements? |
|
Definition
|
|
Term
What does Zn absorption vary from? |
|
Definition
15-40% depending on Zn status |
|
|
Term
2 options for Zn handling once absorbed into intestinal cells? |
|
Definition
Retained within cell for cell functioning Retained within cell by METALLOTHIONEIN to later be released into blood |
|
|
Term
What endocrine organ receives Zn? |
|
Definition
Pancreas
Enteropancreatic circulation of Zn - circulation of Zn from pancreas, to intestine, and back to pancreas |
|
|
Term
Where does Zn loss primarily occur? |
|
Definition
In the feces mainly
Also - skin, hair, sweat, menstrual fluids, semen |
|
|
Term
Major transporter for Zn in the blood? |
|
Definition
Albumin
(some Zn also bound to transferrin instead of Fe) |
|
|
Term
In what populations may Zn deficiency occur? |
|
Definition
Pregnant women, children, elderly, poor
Zn deficiency is rare in developed countries |
|
|
Term
Symptoms of Zn deficiency? |
|
Definition
Hinder digestion & absorption - leading to diarrhea and malnutrition Impaired immune response Change CNS if chronic Affect vitamin A metabolism |
|
|
Term
Zn toxicity can lead to deficiencies in which other minerals? |
|
Definition
Fe and Cu (due to shared binding sites on transporter proteins; excess displaces the other minerals) |
|
|
Term
What are most goitres caused by ? |
|
Definition
LACK of IODINE - to try and make more TSH, thyroid enlarges to form goitre |
|
|
Term
Iodine deficiency during pregnancy may lead to... |
|
Definition
Cretinism in child - mental & physical retardation
Iodine deficiency is the most common cause of preventable mental retardation/brain damage |
|
|
Term
What does Se function mainly with in the body? |
|
Definition
The co-enzyme GLUTATHIONE PEROXIDASE - prevents free radical formation |
|
|
Term
What other mineral does Se share some characteristics with? What does this allow for? |
|
Definition
Se is similar to S
Allows it to take S place in some amino acids (Met, Cys) |
|
|
Term
Selenium deficiency is associated with what disease? |
|
Definition
KESHAN DISEASE - heart enlargement & insufficiency; Keshan likely caused by a virus, but Se deficiency may predispose |
|
|
Term
Copper is necessary for the absorption and use of what other mineral? |
|
Definition
Fe
Cu-containing ENZ catalyze oxidation of Fe2+ (ferrous) to Fe3+ (ferric) - needed for Hb formation |
|
|
Term
Cu containing ENZ have what roles in the body? |
|
Definition
Collagen formation & wound healing Oxidation of Fe2+ -> Fe3+ Protection against free radicals |
|
|
Term
Cu - difference between Menkes and Wilson's disease? |
|
Definition
Menke's = Cu deficiency; intestinal cells ABSORB Cu but DON'T release into circulation
Wilson's - Cu accumulates in liver and brain due to excess |
|
|
Term
What is the route of elimination of Cu? |
|
Definition
|
|
Term
|
Definition
Liver, bones, kidneys, pancreas |
|
|
Term
Why is flouride important in tooth maintenance in structure? |
|
Definition
F replaces OH in hydroxyapetite to make fluorapatite which makes bones stronger/teeth more resistant to decay
Often fluoridate drinking water to increase fluoride intake |
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Term
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Definition
Fluoride toxicity
Leads to discolouration of tooth enamel; occurs ONLY DURING tooth development, cannot be reversed |
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Term
What are the contaminant minerals/heavy metals? |
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Definition
Hg, Pb, Cd - enter food supply by soil, water, pollution
BAD = impair normal body functioning |
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Term
Which contaminant minerals are structurally similar to Fe and Zn? |
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Definition
Pb is similar to Fe, Ca, and Zn - Pb can displace these minerals |
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Term
How many calories are present in 1 pound of body fat? |
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Definition
3500 kcal = 1 pound of fat |
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Term
A healthily weighted adult will have energy stores between ____ and ______ kcal? |
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Definition
between 50,000 and 200,000 kcal |
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Term
What are rapid weight changes in the body usually due to? |
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Definition
FLUID CHANGES (e.g. taking a diuretic) |
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Term
Comparison between LONG TERM and SHORT TERM weight loss? |
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Definition
Long term = 75% fat, 25% lean tissue; (small caloric deficiy; gradual loss)
Short term = 50% fat, 50% lean tissue (severe caloric deficit; much more rapid) |
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Term
Rapid Weight Loss - Yo-Yo Effect Graph... |
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Definition
BOTH fat mass and fat free mass influence how much a person eats
Hyperphagia reaches peak when fat mass falls back to 100%; eating returns to previous levels when fat free mass later gets back to 100% |
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Term
Why does direct calorimetry OVERSTATE the amount of energy the body gets from foods? |
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Definition
B/C the body is not that efficient - direct calorimetry measures all heat produced by bond breaking, the body cannot harness all of this energy |
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Term
Can appetite be experienced without hunger? |
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Definition
YES E.g. want dessert after a big meal, sight and smell of dessert triggers APPETITE not hunger
Appetite prompts a person to eat or not eat! |
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Term
Definition of APPETITE vs. HUNGER |
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Definition
Appetite - integrated response to sight, smell, thought or taste of food that initiates/delays eating; prompts you to eat or not to eat
Hunger - "painful" sensation caused by lack of food that initiates food seeking behavior |
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Term
Why may someone receiving total paraenteral nutrition (TPN) have an appetite but not be hungry? |
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Definition
Are not hungry because they are receiving all necessary nutrients through IV
May complain about appetite because they are not physically eating |
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Term
Relationship between hunger and climate? |
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Definition
Cold = increase food intake
Hot = decrease food intake |
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Term
Anorectic vs. Orexigenic chemicals? |
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Definition
Anorectic - suppresses appetite or promotes weight loss; promotes a NEGATIVE energy balance (e.g. leptin, insulin)
Orexigenic - something that increases appetite or promotes weight gain (increases hunger/intake) |
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Term
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Definition
Feeling of satisfaction and fullness DURING a meal that HALTS eating
Determines how much food is consumed during the meal; occurs when stretch receptors in stomach sense volume |
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Term
Difference between satiation vs. satiety? |
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Definition
Satiation - feeling of fullness DURING meal; tells us to STOP eating
Satiety - feeling of satisfaction AFTER meal; tells us not to start eating again |
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Term
What does satiety determine? |
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Definition
How much time passes in between meals and when we will eat again |
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Term
What is sensory specific satiety? |
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Definition
SSS - phenomenon that we tend to get bored of a food as we eat it; after we eat a food, its pleasantness decreases
More variety in food = more consumption |
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Term
How has it been shown that portion size does matter? |
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Definition
People going to a movie theatre still at 33% more STALE popcorn when it was in a large as supposed to a medium container (larger increase for fresh popcorn)
Large packages & portion size lead to overeating |
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Term
Relationship between feeling of "fullness" and portion size... |
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Definition
Despite the increased intake with larger portion sizes, individuals with larger portions do not report increased levels of fullness! |
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Term
Bottomless bowl study...... |
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Definition
Biased cue (bottomless bowl) vs. accurate cue (normal bowl)
When people estimated the amount of calories they ate comapred to the actual amount, was a HUGE discrepancy for the biased cue (bottomless bowl)
Despite eating more, their estimation of calories was the same as the control group (did not feel any more full) |
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Term
Which energy yielding macronutrient is the most satiating? |
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Definition
PROTEIN (greatest power to suppress hunger & inhibit eating) |
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Term
Besides protein, which other nutrients aid in sustaining satiation? Conversely, which nutrient can stimulate appetite? |
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Definition
Lipids and fibre (both take longer to empty the stomach) maintain satiation
FRUCTOSE (in sugary drinks) can actually stimulate appetite |
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Term
Effect of fat on SATIETY vs. SATIATION |
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Definition
Fat provides LITTLE satiation during meal, but strong SATIETY after the meal when it reaches intestines CCK release in intestines triggers satiety |
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Term
________ correlates directly with a food's satiety |
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Definition
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Term
What type of peptide is Neuropeptide Y in terms of appetite? |
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Definition
It is OREXIGENIC - initiates eating, increases fat storage, causes carb cravings, decreases energy expenditure |
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Term
Where does most energy expenditure come from? |
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Definition
Basal metabolic rate (2/3 of the total E expenditure daily) |
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Term
Total body energy expenditure = ... |
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Definition
Basal metabolic rate Physical activity Food consumption (TEF) |
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Term
What is the general relationship between weight & BMR? |
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Definition
Increased weight = increased energy expended on BMR OVERALL
HOWEVER, amount of energy expended PER POUND may be lower (may be a lower rate per pound, but greater overall expenditure) |
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Term
What is a person's lean body mass equal to? |
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Definition
Weight of the body minus fat |
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Term
What is the effect of environmental temperatures on BMR? |
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Definition
Both heat AND cold RAISE your BMR (BMR increases in either instance) |
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Term
What processes cause BMR to slow down? |
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Definition
Fasting - body conserves fuel stores Malnutrition Age (decrease at 2% per decade) |
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Term
What is the difference between BMR and RMR? Which is generally higher? |
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Definition
BMR has more stringent conditions (12 hour fast, sleep, no activity, comfortable setting), whereas RMR requires less strict conditions on food intake and activity
Usually use RMR in studies; generally RMR is slightly higher than BMR |
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Term
What is the thermic effect of food? |
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Definition
When a person eats, GI tract muscles speed up activity, increased energy produces heat = THERMIC EFFECT
Usually about 10% of intake |
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Term
Thermic effect of food for fats vs. carbs vs. protein vs. alcohol? |
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Definition
Fat = 0-5% Carbs = 5-10% Protein = 20-30% Alcohol = 15-20% |
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Term
Effect of alcohol on appetite? |
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Definition
Usually when sufficient calories are consumed, body decreases appetite - NOT the case with alcohol
Alcohol can stimulate appetite, perhaps through a decrease in leptin levels |
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Term
Why do women generally have a lower BMR than men? |
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Definition
B/c of a lower lean body mass (recall that lean mass burns more calories) |
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Term
Do changes in body weight allow one to assume there has also been a change in body fat? |
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Definition
NOT necessarily. Don't know what composition changed - might be fat, might be lean tissue (water) |
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Term
What is the equation for BMI? |
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Definition
BMI = weight (kg)/ height (m2) |
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Term
BMI ranges for different groupings? |
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Definition
Underweight < 18.5 Normal = 18.5-24.9 Overweight = 25-29.9 Obese > 30 |
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Term
Does BMI reflect body composition? |
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Definition
NO. Just body weight and body height
Therefore, not appropriate if under 18 yrs old, pregnant women, some athletes, etc. |
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Term
High levels of visceral fat are usually called... |
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Definition
CENTRAL OBESITY (intra-abdominal fat accumulation) |
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Term
Difference between visceral vs. subcutaneous fat? |
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Definition
Subcutaenous - directly under skin Visceral - stored w/in abdominal cavity w/ internal abdominal organs |
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Term
What is the most practical indicator of abdominal fat? |
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Definition
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Term
Waist circumference & risk of developing health problems... |
|
Definition
102 cm for men; 90 cm for men of South Asian/Chinese descent
88 cm for women; 80 cm for women of South Asian/Chinese descent |
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Term
Outlines to measuring your waist... |
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Definition
Exhale to let all air out Put tape around waist, between bottom of ribs and top of hips Keep tape parallel to floor |
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Term
What is hydrodensitometry used for? |
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Definition
Measure body density
Weigh person on land, then in water; use equation to calculate body density & body fat |
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Term
People with abnormally high BMI's have the greatest increase in relative risk to which disease? |
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Definition
DMII (for both men & women) |
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Term
Most people with type II DM suffer from _______ obesity |
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Definition
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Term
What is metabolic syndrome? |
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Definition
Diagnosed with a combination of three or more certain health risks: High BP High blood glucose Excess body weight Low levels of HDL High levels of triglycerides
Co-morbid risk factors in this syndrome have a synergistic effect (increases the risk much more when in combination) |
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Term
Increased levels of triglycerides correspond to concentrations greater than....? |
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Definition
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Term
What are considered "low" levels of HDL for men vs. women? |
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Definition
MEN = low is less than 1 mM
WOMEN = low is less than 1.3 mM |
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Term
Overweight people who are physically fit have a lower risk of health problems than normal people who are unfit - TRUE or FALSE |
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Definition
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Term
When does the # of fat cells in the body increase the most rapidly? What happens after this? |
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Definition
During growth spurt of early adolescence
# increases only when there is a positive energy balance
Obese people have MORE and LARGER fat cells than normal weight people |
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Term
Comparaison between fat cells of obese vs. normal weight people? |
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Definition
OBESE people have MORE and LARGER fat cells |
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Term
When you have negative energy expenditure (energy out exceeds energy in) what happens to the #/size of fat cells? Positive energy expenditure? |
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Definition
If negative - the # STAYS THE SAME, but the fat cells shrink
If positive - the fat cells expand first, which signals for the # to increase (get increase in size and #) |
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Term
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Definition
The adverse effects of fat on NON-adipose tissue; damage to other organs of body |
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Term
LPL (lipoprotein lipase) activity in obese vs. normal weight people... |
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Definition
LPL has increased activity in obese individuals, making fat storage more efficient |
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Term
Where is LPL expressed to the greatest extent in women vs. men? |
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Definition
Women - Breasts, thighs, hips (largest fat depositing areas)
Men - Trunk (Abdomen) |
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Term
Why is it more difficult for women to lose fat? |
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Definition
Because basal fat oxidation is lower in women |
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Term
Release of lower body fat in men vs. women? |
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Definition
Release of lower body fat is LESS active in women than in men
Release of upper body fat is the same |
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Term
What is the set point theory and how does it relate to being overweight/obese? |
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Definition
Theory - body tends to maintain a certain set point of the weight by its own internal controls
After weight loss or gain, body adjusts metabolism to RE ATTAIN original weight (after weight gain, expenditure increases; after weight loss, expenditure decreases) |
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Term
What is Prader-Willi Syndrome? |
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Definition
Genetic disorder characterized by excessive appetite, massive obesity & short stature (genetic cause of obesity) |
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Term
Where is leptin produced and where does it act? |
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Definition
Produced by fat cells, acts as a hormone primarily in the hypothalamus |
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Term
What type of hormone is LEPTIN in reference to its effects on energy expenditure? |
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Definition
It is ANORECTIC - decreases appetite, increases energy expenditure = promotes a NEGATIVE energy balance |
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Term
What happens to leptin levels when body fat increases or decreases? |
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Definition
Moves in same direction as change in fat - if increased fat, then increased leptin; and same vice versa |
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Term
Where is Ghrelin produced/where does it act? What are its effects? |
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Definition
Ghrelin is produced mainly by stomach cells, acts in the hypothalamus
Enhances appetite, decreases energy expenditure |
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Term
What are the relative levels of ghrelin before/after a meal? |
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Definition
Levels usually rise before a meal, and fall rapidly following one |
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Term
What is the function of ghrelin? |
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Definition
Maintain a STABLE body weight
High levels - promotes a negative energy balance Low levels - promotes positive energy balance |
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Term
What are the differences in the two types of fat? |
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Definition
White - stores fat for other cells to use for energy Brown - releases stored energy as heat (fat oxidation); very small quantities present (<1% in humans) |
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Term
Environmental causes of obesity... |
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Definition
Over eating Physical inactivity |
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Term
|
Definition
Non-exercise activity thermogenesis; important role in weight management |
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Term
Which mental disorders have the highest mortality rate? |
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Definition
Eating disorders (10-20% die eventually from complications) |
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Term
In women between 15-25, is anorexia or bulimia more prevalent? |
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Definition
Bulimia (3-5%) is more prevalent than anorexia (1-2%)
According to 1993 survey, pretty sure this is outdated |
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Term
Approximately what %age of women will be affected by an eating disorder in their lifetime (lifetime prevalence)? |
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Definition
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Term
What group of individuals are most likely to develop eating disorders (not women)? |
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Definition
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Term
What is the "female athlete triad"? |
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Definition
Syndrome where eating disorders, amenorrhea, and decreased bone mineral density (osteoporosis) are present |
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Term
What % of female athletes will develop amenorrhea? |
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Definition
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Term
What is "muscle dysmorphia"? |
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Definition
Psychiatric disorder concerning obsession with building body mass |
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Term
What is "central" to an anorexia nervosa diagnosis? |
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Definition
Distorted body image (cannot be self diagnosed)
Also need - malnutrition & denial |
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Term
The protein energy malnutrition seen in anorexia nervosa is similar to what other PEM deficit? |
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Definition
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Term
What are the two types of anorexia nervosa? |
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Definition
Restricting type - no binging/purging
Binge/purge type |
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Term
Criteria for diagnosis of anorexia (DSM-IV) |
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Definition
Refusal to maintain healthy body weight; body weight less than 85% of expected Intense fear of becoming fat or gaining weight, even when under weight Disturbance in self perception of body image Amenorrhea (absence of at least 3 straight menstrual cycles) |
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Term
Criteria to diagnose bulimia nervosa (DSM-IV) |
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Definition
Binge eating episodes - eating in a discrete amount of time a larger portion than most would eat, sense of lack of control while eating Recurrent inappropriate compensatory behaviour in order to prevent weight gain Binge eating & compensation occurs on average 2 times per week for 3 months
Two types - purging vs. non purging |
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Term
What are clinical consequences of the binge-purge cycle? |
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Definition
Subclinical malnutrition
Physical effects - tooth erosion, red eyes, calloused hands |
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Term
Contrast binge-eating disorder w/ bulimia nervosa? |
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Definition
In BE disorder, periodic binging with NO purging
Bulimia nervosa - consume less during a binge, less restraint with dieting
Binge eating IS NOT THE SAME as obesity |
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Term
Negative effects of St. John's Wort? |
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Definition
Can inhibit 5-HT uptake, suppressing appetite
Often combined with ephedrine |
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Term
What alkaloids are found in the Ephedra herbs? What are their effects? |
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Definition
Ephedrine & pseudoephedrine - stimulate CNS and CVS; causes bronchodilation in lungs |
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Term
What is ephedrine normally used for in Canada? |
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Definition
Used for short periods of time as a nasal decongestant |
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Term
What is ephedrine warned against being used for? What is it often combined with in these mixtures? |
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Definition
NOT for - weight loss, energy increase, body building, euphoria
Usuall are ephedrine mixed w/ stimulants |
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Term
Effect of laxatives on calorie absorption? |
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Definition
NO DECREASE in cal absorption b/c absorption occurs in upper GI tract |
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Term
What is sibutramine used to treat? Clinical trials showed? |
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Definition
Used to suppress appetite by inhibiting 5-HT reuptake (used to treat obesity)
Taken off market with increased incidence of cardiac adverse effects; saw weight was significantly reduced compared to placebo, but weight was regained when therapy stopped |
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Term
What is orlistat used to treat? What are its functions? |
|
Definition
Used to treat obesity
Inhibits pancreatic & gastric lipase, therefore fats remain undigested and cannot be absorbed
Inhibits fat absorption by about 30% |
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|
Term
What are the thin suction tubes in liposuction called? |
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Definition
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|
Term
What is the "lap band" procedure? |
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Definition
Used to treat obesity
Silicone band is placed at junction between esophagus & stomach; silicone ring is filled w/ saline Gives restrictive & malabsorption method to weight loss - creates a MINI STOMACH by dividing the stomach |
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Term
What GI structures are altered in the Lap Band procedure? |
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Definition
Stomach is divided into a MINI STOMACH (can only hold 2-3 bites of food) by the lap band (silicone ring)
Intestines are cut 1 and 1/2 feet beyond stomach and attached to pouch to connect and give path to food (bypass entire duodenum & part of jejunum) |
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Term
What occurs in the Roux-en-y Gastric Bypass? |
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Definition
Bypasses the duodenum (major site of Ca, Mg, Fe absorption); more food moves into large intestine to be released Digestive juices still produced in lower stomach and move into intestines |
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Term
What is a reasonable weight loss goal? |
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Definition
Between 0.5 to 2 lbs per week
OR
10% body weight loss over 6 months |
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|
Term
To lose 1 lb per week, what is the typical caloric deficit? |
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Definition
-500 kcal per day (below energy needs) |
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Term
What foods are good for people eating for weight loss? |
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Definition
High fibre, low fat foods - have a low energy density (lots of volume, fewer calories) |
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Term
What types of carbohydrates should be avoided for people on weight loss diets? |
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Definition
Refined carbohydrates/sugars should NOT be eaten
Stick to whole grains |
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Term
Problems w/ the cabbage soup diet? |
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Definition
Very little protein Decreased Ca2+ Very low fat (still need essential fatty acids) |
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Term
What is the principle of the volumetrics diet? |
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Definition
Focus on large hot soups w/ lots of vegetables & salads
PRINCIPLE = decreased energy density |
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Term
What negative metabolic effect occurs in LOW carb diets? |
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Definition
KETOSIS
Body uses protein for gluconeogenesis (b/c no carbs); fat changed into ketone bodies (metabolic acidosis)
Increased urine production, lots of water loss, but NOT fat loss |
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|
Term
How does physical activity contribute to energy expenditure indirectly? |
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Definition
Metabolism remains elevated after exercise Long term - more lean muscle develops, which increases BMR |
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|
Term
National Weight Control Registry - what's dat? |
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Definition
Registry of people who have lost at least 30 lbs and kept it off for at least 1 year
42% reported that maintaining weight loss was LESS difficult than losing the weight to begin with |
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|
Term
National Weight Control Registry study... |
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Definition
3 groups of subjects keeping off weight lost - On own, In organization, Liquid formula
Liquid formula group - said weight maintenance was more difficult than losing weight
On own - expended more cal through strenuous exercise
Despite differences, ALL GROUPS maintained weight loss by eating a low calorie diet (1400) and engaging in high levels of physical activity |
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|
Term
In order to gain weight, what should be the energy balance? |
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Definition
+500 kcal per day (surplus) |
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|
Term
Self reporting of height in men vs. women? |
|
Definition
Men more likely to overestimate their HEIGHT |
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|
Term
Self reporting of weight in men vs. women? |
|
Definition
Women more likely to underreport their weight |
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|
Term
Relationship between self-reporting of weight w/ BMI? |
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Definition
Under-reporting tends to increase with INCREASING BMI
See higher obesity & overweight rates in measured vs. self-reported studies |
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|
Term
In 2010 how many adults (percentage & raw number) were considered obese? How does this compare to 2009 data? |
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Definition
18.1 % (4.5 million adults)
UNCHANGED from 2009 |
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|
Term
Change in obesity rates from 2003 to 2010? |
|
Definition
Men = 16% to 19.8%
Women = 14.5% to 16.5% |
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|
Term
Change in overweight rates from 2003 to 2010? |
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Definition
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|
Term
In what provinces were the obesity rates lower vs. higher than the national average? |
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Definition
Lower = Quebec, British Columbia
Higher = Newfoundland, New Brunswick, Manitoba, Saskatchewan |
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|
Term
In both sexes, which age group has the lowest obesity rate? |
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Definition
Between 18 and 19 yrs of age |
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|
Term
In the middle aged groups (20-54) which gender is more obese? |
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Definition
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